Vapor-electric device



Jan.-l7, 1939.

P. L. LENZ 2,144,500 VAPOR-ELECTRIC DEVICE Filed April 21, 1938 3 a/ VeL-l A /4 WITNESSES:

'INVENTOR Peferl. Zen 2.

BY v J 4 SW ATTORNEY Patented Jan. 17, 1939 PATENT OFFECE VAPQR-ELECTRIGDEVICE:

Peter LLLenz, Edgewood, Pa., assignor to Westinghouse Electric &Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsyl-.vaniai 0 Application April 21, 1938, Serial No. 203,362

" 6'Olaiins. 1 (01. 250-215) In the operation of vapor-electric devices,such 'as'mercury arc rectifiers; it is customary to provide a highvacuum pump for maintaining the necessary vacuum for eflicient operationof the device.

Heretofore considerable difliculty has been experienced because of thetransfer of the working vapor between the vapor-electric device and thehigh vacuum pump which is usually of the socalled condensation or'molecular vapor type, in which a pumping'medium such as mercury, isvaporized and "so directed as to entrap foreign gases which are to beremoved from the vapor- 'electric device.

If the connections between the vapor-electric device and the pump aresuch that the working medium is transierred'from the device to the"pump, the pump soon becomes overloaded and is no longer operative,while on the other hand, if the working medium is transferred from thepump tothe vapor-electric device, it also "becomes inoperative and thereis considerable danger that the removal'of the working medium ffromthepump will permit the same to be overheated anddamaged if not completelydestroyed. In either event, it is necessary to shut down the apparatusand either remove orreplace the working medium in the high vacuum pump.

Heretofore, many attempts have been made to maintain or automaticallyremove any excess working material out of the pump chamber. In theapparatus according to my invention, the pumpingconnection issoconstructed as to substantially prevent'anytransfer of Working mediumineither direction between the vapor-electric device and the high vacuumpump.

According to my invention, this is accomplished by providing a two-partor V-type connection, each part comprising a. passage preferably tubularin shape, one of said passages extending upwardly at a gentle slope fromthe vapor-electric device and the other extending upwardly from thepumping device. Preferably both of the pumping passages are ofsufficient size to permit ready passage of non-condensable gases orvapor therethrough. These passages terminate in vapor traps which aresupported adjacent to each other and the connection between the passagesis made by a relatively small, preferably U-shaped tubular connectionextending through the top of the traps and extending adjacent to thebottom wall of the trap and being separated therefrom, preferably by adistance substantially equal to the diameter of the U-shaped connection.Both of the upwardly extending or V passages, as well as the vaportraps, are provided with cooling means for condensing any vapor enteringtherein either from. the vapor-electric device or from the pump 1 I Itis, accordingly, an' object of my invention 5 to provide a pumpingconnection which will substantially eliminate transfer of working mediumin either direction between the vapor-electric device and its associatedhigh vacuum pump;

It is a further object of my invention to 'pro- .1 0 vide a pumpingconnection having a relatively small intermediate passage therein.- I,

' Other objects and advantages of my invention will be apparent from thefollowing detailed description taken in conjunction withthe accompanyingdrawing, in which the single figure is an elevational view partly insection, of a vaporelectric device according to my invention.

In the illustrative embodiment of my'invention, the vapor-electricdevice herein shown as 2 a mercury arcrectifier i having a mercury'cathode 2 and a plurality of cooperating anodes 3, only one of which isshown herein, is connected to a suitable high vacuum pump 4 preferablyofthe vapor type by means of a two-part tubular ,2

passage, one part' 6 of the passage being connected directly to thechamber l to be evacuated and the other portion 1 of the tubularconnection being connected directly to the high vacuum pump 4. 7,3

Both of these portions 6 and l are of conside'rable size, preferably ofthe order of approximately 3" in diameter, so that gases or vapors mayreadily enter therein. 'Each of the tubular pas sages terminates at thetop end thereof in a suit- 35 able mercury or vapor trap 8 and 9. Thetraps 8 and 9 were preferably constructed in the form of a chamberconnected to the end of the passages 6 and. l and have a bottom walllevel with the passage opening so that any material con- 0 densedtherein will flow back into the vessel from which it originated.

In order to condense any vapors entering these connections 6 and I, boththe connections 6 and 1 and the vapor traps 8 and 9 are provided withsuitable cooling elements herein illustrated as cooling coils Illconnected in good thermal contact with the exterior of the tubularconnections 6 and I and with the exterior walls of the vapor traps 8 and9. In order to provide a gas passage 50 between the legs 6 and I of theV connection,

a tubular passage is provided between the vapor traps 8 and 9, saidpassage being relatively small with respect to the passages 6 and I, thetrap chambers 8 and 9 preferably being supported on tained in proximityto each other. Preferably this small diameter connectionB is made of U-shape extending downwardly throughthe tops of each of the trap chambers8 and 9 and extending adjacent to the bottom wall of the trap chamberspreferably terminating a distance from the bottom wall approximatelyequal to the inside diameter of the connection I2.

In the operation of this device any mercury or other Working vaporentering either of the larger connecting passages 6 or 7 will becooledby the cooling device it) applied to the exterior of the same, andmost, if not all, of the vapors will be condensed flowingback from thedevice from which it came. However, any vapor which is not condensed inthe connections 6 and 1 will flow into the traps 8 and 9 and impingeagainst the cooled side walls and be condensed therein flowing backwardthrough the aforementioned tubular connections 6 and 1;

Because of the relatively small diameter of the interconnecting passagel2 and because of the proximity of the mouth of the passage I2 to acooled surface, the working vapors do not enter the smaller passage l2,and consequently there is substantially no transfer of working medium between the vapor electric device I and its accompanying high vacuum pump4.

While for purposes of illustration I have shown and described a specificembodiment of my invention, it will be apparent to those skilled in theart that many changes'and modifications can be made therein withoutdeparting. from the true spirit of my invention or the scope of theappended claimsp I claim as my invention:

1. A pumping connection for connecting a mercury vapor pump to a mercuryarc device comprising a passage'connected to said mercury 'mercury vaporpump to a mercury arc device comprising a passage connected to saidmercury arc device, a second passage connected to said mercury vaporpump, individual mercury traps connected to said passages, a U-shapedpassage connecting said traps, said U-shaped passage a common base platei3 so that they are mainbeing of smaller diameter than saidfirst-mentioned passages and extending into proximity with the bottomwalls of said traps and cooling means applied to said first-mentionedpassages and said traps.

3. A pumping connection for connecting a mercury vacuum pump to anevacuated container comprising two oppositely sloping tubular passagesof sufficient size to permit ready passage of gas and vaportherethrough, the lower end of one or said passages being connected tothe evacuated container and the lower end of the other passage beingconnected to the mercury pump, individualcondensing chambers connectedto the upper ends of said passages, and a relatively small tubularpassage connecting said condensing chambers.

4. An evacuating system for a vapor-electric device comprising a vaporpump, an upwardly inclined passage connected to said pump, an upwardlyinclined passageconnected to said vaporelectric device, each of saidpassages terminating in a vapor trap, means for cooling said passagesand said traps to condense any vapor passing therein, means forsupporting said traps in proximity to each other and a U-shaped passageextending into the topof each of said traps, said extending into the topof each of said traps, said i 'U-shaped passage being smaller incapacity than said first-mentioned passages, said U-shaped passageopening toward the bottom of said traps. I '6. An evacuating system fora vapor-electric devicecomprising a vapor pump, an upwardly inclinedpassage connected to said pump, an upwardly inclined passage connectedto said vaporelectric device, each of said passagesterminating in avapor trap, means for cooling said passages and said traps to condenseany vapor passing therein, means for supporting said traps in proximityto each other and a passage extending between said traps, said passagebeing of smaller capacity than said first-mentioned passages.

' PETER. L.' LENZ.

